1. Field of the Invention
This invention relates to mobile machines for loading debris and other material through the use of a vacuum, and more particularly to such machines as adapted for use in sewer cleaning operations.
2. Description of the Prior Art
Mobile vacuum loading machines are well known in the art. Prior mobile vacuum loading machines have been used in various industrial applications, primarily to provide a means for collecting and storing fairly large amounts of debris, and thereafter transporting the debris to a dump. These machines have often been mounted on truck chassis and/or trailers which are towed by a truck. Mobile vacuum loading machines have often been adapted for use in cleaning sewers and catch basins, and use a high-pressure hose which is inserted into lateral sewers for dislodging debris, and have a large diameter suction hose for removing the debris from the catch basin.
The machine is typically provided with a water tank and a water pump. The water pump has an outlet into a hose reel mounted on the machine with hose coiled on the reel. The water hose is often supported by a swing arm to allow the hose reel to be moved horizontally with respect to the rest of the machine. The hose can be unreeled from the reel and inserted into a catch basin or sewer manhole and into the laterals which require cleaning. The hose reel may be mounted on the front of the machine or on the rear of the machine.
The machine also typically has a vacuum tank with a large diameter movable vacuum hose attached to the tank which may be manipulated in the vicinity of the machine by an operator. The vacuum hose is supported by a boom which is mounted on top of the tank. As debris is flushed from the laterals into the catch basin, the vacuum hose draws the debris into the tank.
After the vacuum tank has been filled, it is typical for prior art loading machines to incorporate a hydraulically actuated dump box and tailgate so that the collected material may be dumped at a convenient site.
Examples of such machines are shown in the following U.S. patents.: No. 4,227,893, issued to Shaddock; No. 4,322,868, to Wurster; No. 4,446,591 to Wiedemann; No. 4,525,277, to Poulin; No. 4,578,840, to Pausch; and No. 4,669,145, to Kehr.
When using prior art loading machines, the placement and location of the machine with respect to the work area was often very important. For example, when using such a machine as a sewer cleaning machine, it was often important to have the machine positioned correctly with respect to the manhole or catch basin so that the hose reel and vacuum boom could be operated efficiently. If the machine was not properly positioned, the operator may have been required to move the machine before performing the sewer cleaning operations.
Thus, it is desirable to utilize a machine in which the boom supporting the vacuum hose can be rotated a full 360.degree. to eliminate the requirement for exact placement of the truck relative to the manhole or catch basin to be cleaned. At the same time, it is also desirable to utilize a machine in which the hose reel is capable of as much horizontal movement as possible with respect to the rest of the machine so that it is not necessary to precisely position the hose reel over the manhole and so that any problems of short bends or kinks in the hose are avoided.
Prior art machines have not been capable of providing 360.degree. rotation in the boom. Similarly, some prior art machines have offered only a limited range of travel of the hose reel from its mounting point, or have provided increased range of travel only at the expense of incorporating lost motion or "slop" in the drive mechanism. Thus, the operator was often required to precisely position the machine in order to operate both the boom and the hose reel within the defined limits of operation of the prior art machines.